By using the concept of equation of a line, that three points $(3,0), (-2,-2)$ and $(8,2)$ are collinear.
Solution:
Given three points $A(3,0), B(-2,-2)$ and $C(8,2)$
Equation of $AB, (y-0) = \frac{0+2}{3+2} (x-3)$
$\Rightarrow y=\frac{2}{5} (x-3)$
$\Rightarrow 5y = 2x-6 \Rightarrow 2x-5y-6=0$